For automotive applications, fasteners are used to join trim pieces to sections or metal body portions of the automobile. The requirements for these fasteners are that they be insertable into apertures of the automobile and meet standards for both insertion pressure of the insert as well as minimum pullout retention force such that the insert can be removed without damaging the trim piece. Common fastener designs include two or more flexible wings which deflect inwardly upon insertion of the fastener and expand by spring force to hold the fastener within a slot formed in the automobile. A drawback of commonly used fasteners is the inability of the fastener to compensate for misalignment between the fastener location and the aperture in the automobile. A further drawback is the inability of commonly used fasteners to accommodate slight rotation of the assembled joint in order to compensate for further misalignment between the fastener and the aperture of the automobile. Still another drawback of some existing fastener designs is an all metal body of the fastener itself. An all-metal fastener can result in corrosion between the metal contact surfaces between the fastener and the automobile as well as causing damage to the area of the aperture of the automobile upon insertion of the fastener or removal of the fastener.
Some fastener designs have a further drawback by requiring two pieces. In one application, a fastener body is insertable into an aperture and a second piece is inserted into the first piece to expand the first piece, thus holding the fastener in position. This obviously increases complexity of assembly as well as requiring the cost and maintenance of a two part system during vehicle construction.